The overall objectives of the Morphology Core Laboratory are to provide expertise, equipment and procedures relevant to GI research, to make available its specialized laboratory facilities to GI researchers, and to develop new tests that may be useful in clinical and basic research. Major core services include histology, immunofluorescent antibody studies, DNA and RNA extraction, transmission, scanning, and immunoelectron microscopy, quantitative morphometric analysis and laser capture dissection for molecular genetic analyses. The core will also provide consultation and training in the proper collection, fixation storage and handling of human and animal tissues, as well as training and technical advice to researchers interested in developing sophisticated procedures for their GI-related research projects. In coordination with Core F (Study Design and Clinical Specimen Core), a bank of human and mouse gastrointestinal and liver tissue, both normal and diseased, will also be created in order t to make these valuable samples available to Center researchers for specific projects, as controls for their studies, and to test new reagents and methods. A major benefit of the Core is to utilize information and expertise gained from diverse projects in individual laboratories to enhance the productivity of all. This will be accomplished by regular meetings of the user group at which new data, methods and procedures will be presented and their applicability to diverse investigations will be demonstrable.